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A012767
E.g.f.: arctan(cosh(x)*tan(x))=x+3/3!*x^3-35/5!*x^5-1057/7!*x^7+59865/9!*x^9...
0
1, 3, -35, -1057, 59865, 5446683, -726781835, -133713611977, 32440474082865, 10034804733270963, -3854719922524818035, -1800259494456990656497, 1004556790822666566963465
OFFSET
0,2
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[ArcTan[Cosh[x]Tan[x]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Aug 01 2012 *)
CROSSREFS
Sequence in context: A287405 A107712 A062699 * A279377 A215582 A136525
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Definition clarified by Harvey P. Dale, Aug 01 2012
STATUS
approved